Finding the Fourth Proportional to 9,621.89, 13,278.17 and 5,430.11

Step by Step Solution

1. Step 1: Write the proportion equation
   9,621.89 : 13,278.17 = 5,430.11 : x
2. Step 2: Convert to fraction form
   9,621.89/13,278.17 = 5,430.11/x
3. Step 3: Cross multiply
   9,621.89x = 13,278.17 × 5,430.11
4. Step 4: Simplify right side
   9,621.89x = 72,101,896.55
5. Step 5: Solve for x
   x = 72,101,896.55/9,621.89
6. Step 6: Final answer
   x = 7,493.53